Carton



Nov. 21, 1961 C- R. KNOX CARTON Filed July 1, 1960 CHARLES R. KNOX nited States Patent 3,009,624 CARTON Charles R. Knox, Downers Grove, Ill., assignor, by mesne assignments, to Chicago Carton Company, a corporation of Delaware Filed July 1, 1960, Ser. No. 40,427 6 Claims. (Cl. 229-39) This invention relates generally to cartons. More particularly, the invention relates to tamper-proof cartons.

It has long been common to package butter or margarine in rectangular one-quarter pound bars or sticks which are individually wrapped in Wax paper or the like, and which are often packaged four at a time in side-byside relationship in a fiat rectangular carton. These packages are usually formed by wrapping a carton blank around a group of four sticks with the endmost panels of the blank in overlaid relation to each other to form one of the narrow side walls. The cartons are usually closed and retained in set-up condition through interengagement of certain of the flaps forming the end closures, and are generally free of any glue or other attachment between the overlaid end wall panels forming the narrow side wall referred to above.

Frequently a shopper wishes to buy less than the four sticks in the butter or margarine package; and shoppers have discovered that the cartons used in the past can be easily opened to remove one or more sticks by pulling on the outer of the endmost overlaid panels, thereby separating the overlaid panels and withdrawing the flaps connected to theouter of the endmost panels from one or both of the end closures so as to generally open up the narrow side wall formed by the endmost overlaid panels. Occasionally a partially" emptied package is reclosed 'by the customer and subsequently sold as a full package. This causes considerable dissatisfaction whenthe partially empty condition of 'thereclosed package is discovered by the purchaser. Moreover, when a number of cartons are opened, the appearance of the self-service freezers or cabinets containing the cartons often becomes untidy, with resultant decreased appeal to the customer.

Accordingly, the invention has for its principal object the provision of a tamper-proof carton. A more specific object of the invention is the provision of a tamper-proof carton for packing four one-quarter pound sticks of butter or margarine. Another object of the invention is the provision of a tamper-proof carton which can be economically fabricated and set-up with existing commercial machinery.

Other objects and advantages of the invention will become known by reference to the following description and accompanying drawings of one embodiment of the invention in which:

FIGURE 1 is a fragmentary plan view of a blank from which a carton incorporating various features of the invention can be erected; and

FIGURE 2 is a fragmentary perspective view of a carton in accordance with the invention.

The carton 5 shown in FIGURE 2 has been erected from the blank 7 shown in FIGURE 1 and comprises a series of four side walls, together with a top end closure, indicated by the numeral 9, and a similar bottom end closure (notsshown). The side walls are provided by a series of integrally formed, hingedly connected panels arranged with the endmost panels of the series in overlying relation to define one of the narrow side walls of the carton, indicated by the numeral 11. The closures at each end are formed by flaps extending from the side wall panels. The tamper-proof advantages of the disclosed construction are provided by the incorporation of means for interlocking the overlaid endmost panels to each other;

and by the incorporation of means for interengagement between the flaps extending from the overlaid endmost panels to prevent withdrawal of these flaps from the end closures.

For purposes of convenience, the blank 7 will first be described in detail, after which, the erection of the carton 5 from the blank 7 will be described. As shown in FIG- ure 1, the blank 7 is generally rectangular in outline, being symmetrical about a lengthwise center line 10, and is formed of paperboard or other like material. The blank 7 includes a series of five integrally connected and ailgned side wall panels 15, 17, 19, 21, and 23, which panels are serially hinged to one another by parallel fold lines 25, 27, 29, and 31'. Extending respectivey from each of the end edges of each of the side wall panels 15, 17, 19, 21, and 23, through a pair of spaced parallel fold lines 33 and 35, are end flaps 37, 39, 4-1, 43, and 45 which, when the carton is erected, are assembled to form the top and bottom end closures. I

One of the tamper-proof features of the invention is provided by forming the endmost side wall panels 15 and 23 with interlocking means, whereby they can be reliably held in closely facing relation to each other when overlaid to provide the narrow wall 11 of the erected carton 5. The interlocking of the endmost panels 15 and 23 in the disclosed manner not only locks these panels against unwanted opening of the carton, but also effectively eliminates bowing of the free longitudinal edge 46 of the outer overlaid panel 15 I Specifically, the endmost panel 15, which is overlaid on the other of the endmost panels 23 to form the wall 11, includes a pair of semi-circular cutlines 47 and 49 which define therebetween a tongue 51 and which are each located in spaced convexly-facing relation to each other, with one end of each cut line generally in tangential relation to the outer longitudinal edge 46 of the endmost panel 15. The other of the endmost panels 23 includes a centrally located, generally U-shaped slit 53 having a pair of spaced legs 55 and 57 and an intermediate or connecting leg 59. The connecting leg 59 of the slit 53 is located generally parallel to the fold line 31 and is spaced from the fold line 31 at a distance approximately equal to the chordal length between the ends of the semi-circular cut lines 47 and 49. The legs 55 and 57 extend from the intermediate leg 59 in converging relation to each other toward the outer free edge 61 of the endmost panel 23. The maximum width between the spaced legs 55 and 57 at a point adjacent the connecting leg 59 is at least about equal to the width of the tongue 51 at .the longitudinal edge 46 of the endmost panel 15, i.e., the dimension indicated at A..

When the panels 15 and 23 are overlaid with respect to one another to form the'narrow side wall 11, the tongue 51 is inserted into the slit 53, so that the portions defined by the semi-circular cuts 47 and 49 are in overlying relation to the endmost panel 23 while the'tongue 51 is locked in underlying relation to the endm dg't panel 23. Accordingly, the overlaid endmost panel 15 is retained in closely engaging relation to the inner of the overlaid panels 23. p

Opening of the narrow side wall 11 formed by the overlaid panels 15 and 23 is also prevented by the formation of the flaps 37 and 45 extending from the endmost panels 15 and 23 with interlocking means'for prevent- 1 ing their withdrawal from the end closures. Specifically, the flaps 37 and 45 are each generally square, having side dimensions corresponding to the width of the endmost wall panels 15 and 23. In addition, each ofthe flaps 37 includes an integral tab 63 projecting from the outere'nd of its left side edge, as seen-in FIGURE 1.

Each of the'other flaps 45 includes'an integral ear 65' extending from its left'si'de edge, asseen in FIGURE 1,

along a fold line 67 in general alignment with the fold line 31. The ears 65 are spaced from the outer ends of the flaps 45 at a distance corresponding to the width of the tabs 63, so that, when the flaps 37 and 45 are overlaid during formation of the end closures, the ears 65 can be folded over the edges of the flaps 37 inwardly of the tabs 63, as seen in FIGURE 2. As shown, each of the flaps 45 is cut away at the outer end of its right side edge, as indicated by the numeral 69 in FIGURE 1, to provide tabs 63 for the blank cut from the adjoining material, without waste of paperboard.

The flaps 39 and 43, extending respectively from the side wall panels 17 and 21, are provided with interlocking means for interconnection in overlaid relation to each other to complete the formation of each of the end closures. Specifically, each of the flaps 39 includes a pair of spaced locking tongues 71, While the flaps 43 each include a pair of slits 73 which are located for interengagement with tongues 71. In addition, the right side edges of the flaps 43, as seen in FIGURE 1, are cut at an acute angle to the fold lines 33 and 35 to facilitate formation of the ears 65 extending from the adjacent flaps 45.

Means are also included in the blank 7 to facilitate opening of the carton after it is sold. This means is provided by forming the fold line 33 with a pair of perforated line segments 75 extending respectively, between the side Wall panels 17 and 21 and the flaps 39 and 43. Each of these segments 75 extends from adjacent the side wall panel 19 and has a length which is longer than the height of the flap 41. Thus, when the carton 5 is erected, the flaps 39 and 43 can be partially torn from the side wall panels 1'7 and 21 to expose the underlying flap 41, which flap 41 can then be swung outwardly of the carton 5 to provide access to the sticks of butter or margarine enclased therein.

The carton 5 is erected by forming the side wall panels 15, i7, 19, 21, and 23 into tubular relation with the wall panel in overlaid relation to the wall panel 23 to form the narrow side wall 11. The tongue 51, as previously mentioned, is then preferably engaged within the slit 53 to retain the overlaid wall panels 15 and 23 in closely engaging relation to each other. Forming of either of the end closures can then be initiated by inwardly folding the flap 41 and the flaps 37 and 45. In this regard, the flaps 37 and 45 extending from the endmost panels 15 and 23 are folded inwardly in generally coextensive relation to each other with the flap 37 in overlaid relation to the flap 45 and With the ear 65 projecting outwardly from the flap 45 in adjacent relation to the inner side edge of the tab 63 extending from the flap 37.

The flap 43 is then folded inwardly carrying the car 65 into overlaid relation to an edge portion of the flap 37 located inwardly of the tab 63. When thus positioned, the flap 37 is restrained from displacement outwardly of the end closure by engagement of the edge of the tab 63 with the edge of the car 65 at a point adjacent the fold line 67. Finally, the remaining flap 39 is' folded into overlying relation to the flap 43 and secured thereto by locking insertion of the tongues 71 into the slits 73.

With the flaps 39 and 43 thus secured, they serve the dual purpose of retaining the end closures in assembled condition and of maintaining the ears 65 in folded overlying relation to the flaps 37 for engagement with the tabs 63 to prevent outward displacement of the flaps 37 from the end closures.

The. carton 5 thus constructed includes two anti-tampering features, each of which provides efiective resistance to unwanted opening of the carton by the customer prior to the time of sale. In combination, these features provide a tamper-proof carton which cannot be opened by separating the overlaid panels 15 and 23 without mutilation of the paperboard and which is also neat in appearance due to the close engagement of the overlaid panels 15 and 23.

Various of the features of the invention are set forth in the following claims.

What is claimed is:

l. A carton comprising a series of side walls provided by a series of integrally and hingedly connected panels arranged with the endmost panels in said series in overlying relation to each other to define one of said side walls, a closure at one end of said side walls provided, at least in part, by flaps extending in overlying relation to each other from each of said endmost panels, and mutually interlocking means on said flaps for preventing relative displacement outwardly of said end closure of one of said flaps as compared to the other of said flaps.

2. A carton comprising a series of side walls provided by a series of integrally and hingedly connected panels including at least three intermediate panels and two endmost panels, said panels being arranged with the outer two of said three intermediate panels in opposed relation to each other and with the endmost panels in overlaid relation to each other to define said side walls, a closure at each end of said side walls provided by flaps extending in overlaid relation to one another from each of said two opposed panels and said endmost panels, mutually interlocking means on each of said flaps extending from said two opposed panels for retaining the mutually overlaid relationship of said flaps defining said end closures, mutually interlocking means on said flaps extending from said endmost panels for preventing relative displacement outwardly of said end closures of one of said flaps extending from said endmost panels as compared to the other of said fiaps extending from said endmost panels, and mutually interlocking means on each of said endmost panels for holding said endmost panels in closely overlaid relation to each other.

3. A carton comprising a series of side walls provided by a series of integrally and hingedly connected panels arranged with the endmost panels in said series in overlying relation to each other to define one of said side walls a closure at one end of said side walls provided, at least in part, by flaps extending in overlying relation to each other from each of said endmost panels, an ear extending outwardly of the side edge of the outer of said overlaid flaps, and a rebent tab extending from the inner of said overlaid flaps in overlying relation to a portion of said outer fiap and in position to engage said ear to maintain said side walls in overlaid relation to each other and to prevent displacement outwardly of said end closure of said outer flap.

4. A carton comprising a series of side walls provided by a series of integrally and hingedly connected panels arranged with the endmost panels in said series in overlying relation to each other to define one of said side walls, a closure at one end of said side walls provided by a flap extending from each of said endmost panels in overlaid relation to each other, and a flap extending from one of the other panels in said series and secured in overlaid relation to said flaps extending from said endmost panels, an ear extending outwardly of the side edge of the outer of said flaps extending from said endmost panels, and a tab extending from the inner of said flaps extending from said endmost panels, said tab being folded into overlaid relation to a portion of the outer of said flaps extending from said endmost panels and being retained in said overlaid condition by said flap extending from said one of the other of said panels in said series, the edge of said tab being in position to engage said ear so as to prevent displacement outwardly of said end closure of said flaps extending from said endmost panels.

5. A carton comprising a series of side walls provided by a series of integrally and hingedly connected panels including at least three intermediate panels and two endmost panels, said panels being arranged with the outer two of said intermediate panels in opposed relation to each other and with the endmost panels in said series in overlying relation to each other to define said side walls, a closure at each end of said side walls provided by flaps extending in ovenlaid relation to one another from each of said two opposed panels and said end-most panels and with said flaps extending from said two opposed panels being overlaid with respect to said flaps extending from said endmost panels, an ear extending outwardly of the Side edge of each of the outer of said flaps extending from said endmost panels, a tab extending from each of the inner of said flaps extending from said endmost panels, said tabs being folded in overlaid relation to a portion of the outer flaps extending from said endmost panels and in position to engage said ears to prevent displace ment outwardly of said end closures of said flaps extending from said endmost panels, and mutually interlocking means one each of said flaps extending from each end of said two opposed panels for retaining said flaps extending from said two opposed panels in overlaid relation to each other and for retaining said tabs in overlaid relation to the outer flaps extending from said endmost panels.

6. A carton comprising a series of side walls provided by a series of integrally and hingedly connected panels including at least three intermediate panels and two endmost panels, said panels being arranged with the outer two of said intermediate panels in opposed relation to each other and with the endmost panels in said series in overlying relation to each other to define said side walls, a closure at each end of said side walls provided by flaps extending in overlaid relation to one another from each of said two opposed panels and said endmost panels and with said flaps extending from said two opposed panels being overlaid with respect to said flapsextending from said endmost panels, an ear extending outwardly of the side edge of each of the outer of said flaps extending from said endmost panels, a tab extending from each of the inner of said flaps extending from said endmost panels,

said tabs being folded in overlaid relation to a portion of the outer flaps extending from said endmost panels and in position to engage said ears to prevent displacement outwardly of said end closures of said flaps extending References Cited in the file of this patent UNITED STATES PATENTS 1,767,734 Brown June 24, 1930 FOREIGN PATENTS 3,040 Great Britain Mar. 17, 1900 UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent No. 3,009 624 November 21 1961 Charles R. Knox Column 3, line 36, for "enclased" read enclosed column 5, llne 14, for "one" read on Signed and sealed this 24th day of April I962.

(SEAL) Attest:

ESTON G. JOHNSON DAVID L. LADD Attesting Officer Commissioner of Patents 

